From: Jean-Hugues ROBERT <jean_hugues_robert@...>
Date: 2002-06-11T01:27:26+09:00
Subject: RE: multiple instances of Ruby interpreter in my C++ code?

Hello,

At 23:24 10/06/2002 +0900, you wrote:
>To be honest, I've never really seen the point of cooperative
>multi-tasking.

When making the code "thread safe" is not worth the trouble, it
becomes handy to revert to cooperative multi-tasking. Not to
mention that the code is much easier to debug (race condition bugs
are very much the modern equivalent of the old C dangling pointer
of the past, in terms of difficulty to debug them, to me).

BTW: closures make it much less useful to use preemption, you
achieve the same simplicity/readability with them than with
threads, often, IMO.

About embedding Ruby, I would prefer it to be as easy as it is
for other languages, Tcl for example. The more Ruby users, the
better I feel ;-)

Maybe the multiple instances of Ruby interpreter can be workarounded
with load( file, private_flag), where private_flag deals with
namespaces... I don't know if there is some equivalent for eval()
but I am pretty sure that by enclosing the code inside a "begin"/"end"
the local variables are going to be "local" to each "instance".

Switching from one ruby "thread" to another is a matter of calling
the underlying multi-tasker "yield()" function I guess

Conclusion: With cooperative multi-tasking, multiple instances of
Ruby interpreter can be "simulated". There are probably some data
with "global" scope that need some more handling and that I am
overlooking.

Yours,

Jean-Hugues